Devices of the type described are previously known and are usually used for cleaning circuit boards on which electronic components are or have been mounted, for example by soldering, with the device serving to guarantee satisfactory solder connections and to remove flux residue and the like.
Previously known devices have proved to function rather well with regard to cleaning effect, but problems have arisen because solvent evaporates from the vessel and contaminates the atmosphere. This both presents a health hazard for operators in the workroom, and involves a significant loss of solvent. To prevent the solvent from contaminating the atmosphere of the workroom, it is usual to draw off the air above the device and lead such solvent-saturated air through a charcoal filter, for example. Such charcoal filters are, however, costly both as regards construction and operation, especially in view of the fact that devices of the present type are not normally used continuously but must in any case be kept in readiness, and the fact that the filters must be large in size. Even if it is possible to recover the major portion of the solvent from the charcoal filter, relatively high costs are involved.